1. Field of the Invention
The present invention relates to a tool arrangement with a tool unit, e.g. a cutting apparatus, a spreader, a squeezing device or the like, and with a control and/or switching element, a drive, as well as a first operating-medium circuit.
2. Description of the Prior Art
Tools that must transfer large forces, as for example cutting tools, squeezing devices, and the like, are known. Such tools are therefore frequently equipped with a hydraulic or pneumatic drive, which, for example, effects an opening and closing movement of a spreader or a shearing device.
A tool of this type results from, for example, DE 692 21 221 T2, which tool displays a hydraulic cylinder, the lifting rod of which actuates the actual tool, which is formed by two cutting edges or two arms. The hydraulic drive, in this particular case, is operated by means of a compressible fluid.
Hydraulic fluids are in most cases a matter of incompressible oils, due to the corrosive characteristics of water. However, the case can also arise in which a diminishing in size or processing of diverse parts must take place under water. Thus, for example, in nuclear power stations or reactors it is necessary to crush parts under water, because the space for storage of the irradiated material is to be kept as small as possible. In the case of a leak in the tool, all of the water, which here concerns in particular deionized water (deionate), must be purified, which is associated with high costs.